Spermatophore Generation Times in<i>Penaeus setiferus, P. vannamei</i>, and<i>P. stylirostris</i>

Leung‐Trujillo, Joanna R.; Lawrence, Addison L.

doi:10.1111/j.1749-7345.1991.tb00741.x

Cited by 33 publications

(14 citation statements)

References 19 publications

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“…Similar high mortality were observed by several researchers, [34][35][36] who studied the effect of unilateral and bilateral eyestalk ablation in decapod crustaceans. Furthermore, the pattern depicts that the increase was gradual during the progression of the CGE-1 administration at higher doses of CGE-1.…”

Section: Effect Of Cge-1 On Weight Gain Molt Frequency and Incrementsupporting

confidence: 85%

Effect of a novel compound as dietary supplement on growth of decapod crustaceans

Shrivastava

Princy

2015

RSC Adv.

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Several conventional methods have been used for many years to accelerate the growth in decapod crustaceans but they are suitable for aquaculture practices due to their harmful effects on the animals. The concern over water quality, environmental hazard, human health and food safety has led us to a search for alternative targets to design growth enhancers which can significantly improve the growth of crustaceans without harmful effects. Among such compounds has been CGE-1, an amine compound which have shown excellent molt inducing property. The lobsters treated with CGE-1 exhibited a higher weight gain and greater increment in the carapace length post-molt as compared to the controls even without inhibiting the synthesis and secretion of molt-inhibiting hormone (MIH). This is a significant finding considering the fact that MIH bind specifically to the membrane receptor of y-organs, hence CGE-1 might interferes with this interaction allowing an incessant production of 2-hydroxyedysone (20E). Here, we summarize our findings on the CGE-1 and its effects with particular focus on inclusive growth and vitellogenesis. Our observations and findings suggest that CGE-1 could be a useful growth enhancer that could be used either alone or as a dietary supplement for the rapid growth of decapod crustanceans.

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Section: Effect Of Cge-1 On Weight Gain Molt Frequency and Incrementsupporting

confidence: 85%

Effect of a novel compound as dietary supplement on growth of decapod crustaceans

Shrivastava

Princy

2015

RSC Adv.

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“…Manually or electrically ejaculating the spermatophores can also remove melanin debris from the ampoules, and many studies use these methods to keep males in good condition in the absence of females. Indeed, most of these studies reported that, over extended time periods, spermatophores did not show deterioration (Leung-Trujillo and Lawrence, 1991;Alfaro, 1993;Alfaro and Lozano, 1993;Heitzmann and Diter, 1993;Pratoomchat et al, 1993;Alfaro, 1996;Pascual et al, 1998;Diaz et al, 2001;Ceballos-Vazquez et al, 2004). If the spermatophores are not evacuated (manually, electrically or through mating), they may become melanized in some individuals even within few days (as in Fig.·2) and subsequently hardened enough to prevent their ejaculation (Leung-Trujillo and Lawrence, 1987;Talbot et al, 1989;Perez-Velazquez et al, 2001).…”

Section: Discussionmentioning

confidence: 99%

“…In many decapod crustacean species, such as shrimps, lobsters and crabs, female reproduction is synchronized with the molt cycle and is thus cyclic by definition (Adiyodi, 1985;Nelson, 1991). The nature of the association between molt cycles and reproduction in decapod males is, however, not known, although a few clues do exist, all of them from penaeid shrimp: manually ejaculated Litopenaeus vannamei exhibited new pairs of spermatophores in their ejaculatory ducts (ampoules) only after molting (Heitzmann and Diter, 1993); a decline in spermatophore quality as the molt cycle progressed was observed in Fenneropenaeus indicus (Muthuraman, 1997); and naturally mating L. vannamei and L. setiferus were shown to be carrying new pairs of spermatophores a few days after mating within the same molt cycle that the mating had occurred (Leung-Trujillo and Lawrence, 1991). Whereas these are the only reported indications of an underlying periodic reproductive mechanism…”

Section: Introductionmentioning

confidence: 99%

Males also have their time of the month! Cyclic disposal of old spermatophores, timed by the molt cycle, in a marine shrimp

Parnes

Raviv

Shechter

et al. 2006

Journal of Experimental Biology

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SUMMARY That sexually mature females go through hormonally regulated reproductive cycles is a well-established phenomenon in sexually reproducing organisms. Males, on the other hand, are commonly regarded as being continuously ready to mate. `Programmed sperm degradation' on a periodic basis or an innate sperm`expiry date' have never been shown. This manuscript describes a newly discovered molt-dependent mechanism by which old sperm is periodically removed from the reproductive system of male Litopenaeus vannamei shrimp. Firstly, it is shown that the spermatophores of males held in captivity become progressively melanized, a process that eventually renders them impotent. Then, by using melanin specks as a color marker, it is demonstrated that this phenomenon can be delayed and even reversed as long as the males remain sexually active. Lastly and most importantly, it is shown that male shrimp go through reproductive cycles that are strictly associated with their molt cycles, which, in turn, are hormonally regulated. Intact intermolt spermatophores disappeared about 12 h premolt, and a new pair of spermatophores appeared in the ampoules the day after the males had molted. This phenomenon was observed in an almost constant portion of males, both those in an all-male population and those in mixed male/female populations,even during the times that the females of those populations were not vitellogenically active. To the best of our knowledge, this is the first report of males of any animal species exhibiting endogenous reproductive cycles, as do females, and of the finding that spermatozoa have a predetermined expiry date, a feature that may possibly contribute to male fitness.

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“…The sperm count and the record of the proportions of live/dead and normal/abnormal sperm morphology estimations were made by macerating the spermatophores in 0.5 ml of distilled water and staining the river prawn sperm with eosin‐nigrosin in 1.5 ml Eppendorf tubes (Viana da Costa et al, ). The sperm count was assessed using a Neubauer camera and observed with an optical microscope at 10, 20, 40 and 100× magnification (Leung‐Trujillo & Lawrence, ). Sperm concentrations were reported as the number of sperm per microlitre (sperm/μl).…”

Section: Methodsmentioning

confidence: 99%

Spermatophore production and sperm quality of the river prawn Macrobrachium americanum Spence Bate, 1868 fed with different diets

et al. 2019

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The effects of different diets on spermatophore production and sperm quality were investigated in the river prawn Macrobrachium americanum. River prawns were cultured and fed with three diets for 244 days: fresh food (50% squid meat, Dosidicus gigas and 50% sardine muscle, Sardinops sagax); commercial pellets (35 Purina®); and a 50:50 mixture of both diets. Spermatophore production was recorded every 24 days on average as the percentage of spermatophores produced per extraction per diet, weight and biochemical composition. Sperm quality was measured as the total number of sperm, the proportion of live/dead sperm and normal/abnormal sperm morphology. There were no significant differences in the mean biochemical composition of M. americanum spermatophores for any of the diets. Biochemical composition was 36.3% protein, 25.8% carbohydrate and 4.6% lipids for all data pooled. The weight of spermatophores and sperm counts was not significantly different among diets, nor were there any differences as a function of the male initial total length (p > .05). Male river prawn reproductive exhaustion was observed as a decline in spermatophore production, weight of the spermatophores and the number of sperm cells per spermatophore, with an increasing proportion of dead and abnormal sperm seen throughout the experiment. The recommended period of maintenance in captivity for male broodstock is less than 115 days. It is recommended to feed broodstock males of M. americanum with commercial pellets because no significant differences were detected with the diets tested; pellets are easier to use, ensuring the same spermatophore production and sperm quality that was obtained with fresh food.

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Spermatophore Generation Times inPenaeus setiferus, P. vannamei, andP. stylirostris

Cited by 33 publications

References 19 publications

Effect of a novel compound as dietary supplement on growth of decapod crustaceans

Effect of a novel compound as dietary supplement on growth of decapod crustaceans

Males also have their time of the month! Cyclic disposal of old spermatophores, timed by the molt cycle, in a marine shrimp

Spermatophore production and sperm quality of the river prawn Macrobrachium americanum Spence Bate, 1868 fed with different diets

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